import moment from 'moment';
//开始时间结束时间
function getDefaultDateRange(){
  const currMonth = moment().month();
  const currYear = moment().year();
  let startDate = null;
  let endDate = null;

  if(currMonth == 0){
    startDate = currYear - 1 + '-01';
    endDate = currYear - 1 + '-12';
  }else{
    startDate = currYear + '-01';
    endDate = currYear + '-' + moment().month(currMonth - 1).format('MM');
  }

  return {
    startDate,
    endDate,
  }

};
//千分位符
function commafy(num, char) {
  num = num + "";
  var re = /(-?\d+)(\d{3})/;
  char = char || ',';
  while (re.test(num)) {
    num = num.replace(re, '$1'+ char +'$2');
  }
  return num;
}
//加
function floatAdd(arg1,arg2){
  var r1,r2,m;
  try{r1=arg1.toString().split(".")[1].length}catch(e){r1=0}
  try{r2=arg2.toString().split(".")[1].length}catch(e){r2=0}
  m=Math.pow(10,Math.max(r1,r2));
  return (arg1*m+arg2*m)/m;
}

//减
function floatSub(arg1,arg2){
  var r1,r2,m,n;
  try{r1=arg1.toString().split(".")[1].length}catch(e){r1=0}
  try{r2=arg2.toString().split(".")[1].length}catch(e){r2=0}
  m=Math.pow(10,Math.max(r1,r2));
  //动态控制精度长度
  n=(r1>=r2)?r1:r2;
  return ((arg1*m-arg2*m)/m).toFixed(n);
}

//乘
function floatMul(arg1,arg2)   {
  var m=0,s1=arg1.toString(),s2=arg2.toString();
  try{m+=s1.split(".")[1].length}catch(e){}
  try{m+=s2.split(".")[1].length}catch(e){}
  return Number(s1.replace(".",""))*Number(s2.replace(".",""))/Math.pow(10,m);
}

//除
function floatDiv(arg1,arg2){
  var t1=0,t2=0,r1,r2;
  try{t1=arg1.toString().split(".")[1].length}catch(e){}
  try{t2=arg2.toString().split(".")[1].length}catch(e){}

  r1=Number(arg1.toString().replace(".",""));

  r2=Number(arg2.toString().replace(".",""));
  return (r1/r2)*Math.pow(10,t2-t1);
}

export default {
  getDefaultDateRange,
  commafy,
  floatAdd,
  floatSub,
  floatMul,
  floatDiv
}
